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What is a movement guide?

A movement guide controls the thermal motion of the piping system into the bellows

What is an expansion coupling used for?

Expansion couplings are used mainly to connect two pieces of pipe together.

How thick are internal liners for bellows?

Usually, the liner material can be the same as the system pipe material, such as carbon steel, with liner thicknesses of 1/8-inch ...Continue Reading

How do you restrain the growth of a bellows?

The growth of an expansion joint bellows is restrained with the use of limit rods.

What is an internal liner?

Internal liners are an expansion joint accessory used to protect the convolutions from direct flow impingement, which can cause erosion ...Continue Reading

For a simple bellow, are the tie-rods main purpose to take the pressure thrust?

Yes for a simple bellow, the tie-rods main purpose is to hold the pressure thrust.

How do you handle pressure thrust in a piping system?

Pressure thrust can be absorbed by placing anchors in a system or by using an expansion joint with tie rods.

What is a directional anchor on a bellows?

A directional anchor restrains the pressure thrust from the expansion joint and allows for movement in a direction perpendicular to the pressure ...Continue Reading

Why do the universal expansion joints need to be tied?

The tie rods are used to take the pressure thrust forces. Most universal expansion joints use tie rods to eliminate the requirements ...Continue Reading

What is meant by pantographic linkage?

Pantographic linkage is an accessory that is used to distribute axial movement between two bellows, allow lateral motion and support the ...Continue Reading

How many tie rods should you use for an expansion joint?

The number of tie-rods used is determined by the design pressure of the expansion joint. It can range from two to ...Continue Reading

What is the purpose of the control rods in an expansion joint?

Control rods are used to control axial and lateral movements of the expansion joint.

When do you use limit rods on expansion joints?

Limit rods are used to limit axial expansion or compression to prevent the bellows from over-compression. Limit rods are designed to ...Continue Reading

What is the purpose of tie rods on an expansion joint?

A common question when designing piping systems is “What do tie rods do to protect the infrastructure?” In systems that ...Continue Reading

Is the bellow really being compressed or is the entire bellow moving?

When there is an axial movement, the in-line bellows will start compressing and the balancing bellows will extend and vice versa. ...Continue Reading

Can axial as well as lateral expansion be absorbed together in a single bellows design?

Yes, axial as well as lateral expansion joints can be absorbed together in a single bellows design, but the lateral movement ...Continue Reading

Can I use an axial expansion joint to absorb pipe expansion with gap inside tie rod nuts without passing thrust on the equipment?

No, you cannot use an axial expansion joint because thrust force will be acting until the gap is closed between the tie ...Continue Reading

For a higher pressure system, how do you absorb pipe axial displacement without pressure thrust going to equipment with use of the expansion joint?

How do you design universal bellows with two different sizes?

The preferred method to design universal expansion joints would be to use a larger diameter bellows and use a reducer at the ...Continue Reading

How do I decrease thrust force in an axial expansion joint?

To decrease the thrust force in an axial expansion joint you must decrease the height of the bellows. However, this method will ...Continue Reading